appendix a: the heir exterminator
by Phoenix Satori
Summary: a combat maneuver origin story: or, how the mad bomber falls for the moon.


welcome to the 'feat equal' extended universe!

this can absolutely be read as a self-contained story, but it *actually* exists as supplemental material for chapters four and five of 'a feat equal,' both of which make reference to the titular kacchako combo attack. there're also little, subtler threads that tie this fic into the larger series, events or Significant Looks and the like that'll payoff later. ;)

enjoy~!

* * *

 **Appendix A: the heir exterminator**

 _(see also: 'whiplash')_

[the cherished memory of beat-downs past: one year prior]

The 'Whiplash' is a move Katsuki dreams up on the fly, once upon a doubles death match (or, as everyone else calls it, a 'charity exhibition match').

The fight's building to a climax when Uraraka overshoots her mark –Todoroki—by half the shitting stadium, and Deku wads Katsuki up like trash and chunks him right along after her. They both easily avoid a crash landing, but Katsuki has to take an unwitting knee when he finally drags to a halt, his _whole body_ wracked by the aftershocks of a punch pulled _just_ shy of rupturing bones or organs. He smirks, vaguely approving even as he spins through his wheel of options for crushing Deku outright. Except, he has to keep reminding himself, fights with Deku work best when he doesn't go in with a plan, since there's less room that way for the eternal fucking fanboy to figure him out.

Needing a way back across the arena _yesterday_ , he snags Uraraka out of his pink-cheeked periphery and fastens her against him, facing outward. He's every bit as unconcerned by the optics of this arrangement as Uraraka herself, who follows his lead without missing a beat. She taps away his gravity when he holds his free hand out behind him, and taps away her own gravity while Katsuki zeroes in on the Lord of the Nerds, whose expression (magnified just behind Deku on a huge-ass video screen) flickers with an aggravating flash of inscrutable - _something_ _-_. In spiteful want of fucks to give, he tucks Uraraka in tight and waits for her to exhale before intentionally backfiring to drive them forward. _**Fast**_.

In the cross-section of an instant, Katsuki sees Deku subtly lowering himself to intercept them, because why bother to dodge when you're the irresistible force _and_ the immovable fucking object? Inspiration strikes like lightning, and Katsuki slams on the brakes, this time firing a forward burst with precisely enough power to bring them up _maybe_ a meter short of torpedoing into Deku. The abrupt deceleration inadvertently snaps Uraraka's head back, _hard_ –which he's sure to catch pouty-faced hell for later— but other than the short, shocked ' _wah_!' she issues and the pointless, guilty churn of his guts in response, Uraraka rolls readily along with his improvisation –literally. Katsuki gives her a firm, downward shove between her shoulder blades to guide her into a somersault, noticing as he simultaneously springboards off of her into the air that Deku's gone full fucking lightshow.

From there, three separate trajectories converge in the most magical way: Katsuki blasts himself into a downward, arcing backflip to come up behind Deku, positioning him to attack from a point above and roughly opposite Uraraka. At the same time, Deku pushes off one foot, briefly approximating a glowing, green streak as he surges forward to avoid the brush stroke of nitrous flame Katsuki sweeps at his back. Meanwhile, Uraraka's rolling out of her tumble, coming up on one knee with her left fist already winding into a solid jab. Deku deftly skirts the blow, which overbalances her weightless body and hurls her sideways –directly, _fortuitously_ , into Deku's slant-ward evasion path.

In the split-second between Uraraka's punch absolutely, _definitely_ connecting and Deku crumpling to the floor like cast-off laundry, the swell of raw anticipation rises in Katsuki's chest.

Deku fails to get back up, instead dropping to his knees, curling protectively around himself, and producing a sound uncannily like air escaping a balloon. And if _that's_ not proof enough that Uraraka's just made one of his most dearly-held dreams come true, the instant replay irrefutably confirms it. On one of the stadium's enormous screens, in glorious slow motion, Katsuki witnesses the _shattering_ fist-to-nuts collision with equal parts reverence and vicarious pride. The image of Deku's bug-eyed, puff-cheeked face as this happens is one he will carry with him forever and always.

Uraraka, clearly not as happy at this turn of events, throws herself at Deku and frets over him helplessly, apologizing over and over again in tones increasingly loud and panicked. Cruel delight rips out of him in the form of a roaring cackle, and in the tellingly frigid seconds before roughly a glacier's worth of ice slams into him –in his joy, he's forgotten all about Deku's _barely_ more tolerable other half—Katsuki's visited by some species of short-lived, benign hemorrhage that has him seeing Uraraka in full-on fucking sparkle vision.

/-/

Following the fight, an overly-enthusiastic journalist practically shoves her recorder in their faces and slaps out a question before he has the chance to politely invite her to fuck off and die.

"What do you call that _sensational_ move you used to take down _The_ Deku?" Katsuki distinctly hears the aggressive reporter capitalizing 'the' when she says it, like the nerd's kiddy-ass-nickname-turned-hero-handle is an imperial fucking _title_. Annoyed purely out of habit, he's about to improvise a fitting tag for the combo –like maybe the 'Flanking Double Doom Backflip,' or the 'Fuck You Special,' or _—_ oh, shit, _epiphany_ : the ' **Heir Exterminator** ;' but Uraraka beats him to the punch, casually reaching up to clap her hand over his mouth as she answers,

"The ' _Whiplash_ ,'" with a cheerful, sunshine smile made entirely of daggers.

/-/

Katsuki's _there,_ bedside, when Uraraka's leopard-eared doc confirms she's sustained a whiplash injury, so when she petulantly accuses him of 'breaking her neck' and demands all damages be paid in mochi, he glibly flips her off and offers to _actually_ break her neck to give her some perspective. Uraraka pouts affectedly and swipes at him, fingertips first, but the sudden movement earns her only wincing pain and an immediate admonishment from the doc. Mindful of _not_ exacerbating her sprain, Katsuki deliberately doesn't lean away to avoid the swing, so her fingers do make contact with his arm, but the landing's more a kind of falling grab than jokey vengeance swat.

"Airhead." He pronounces with commanding finality, ignoring the surprise stab of conscience that accompanies her intake of breath and pinched recoil. He can cop to an inadvertent and _partial_ share of the responsibility, but he refuses to feel guilty about field mishaps. In spite of exceptional, crucible-honed instincts and top-tier mechanical sense, shitty mistakes _do_ occasionally happen. He'd sooner swallow fire than admit as much out loud, but it's a reality he secretly values for its implication: if he's still –but like, _rarely_ —capable of careless fuckups, it means he hasn't hit his upper limit yet, which _itself_ means he's still got plenty enough growth potential to overtake the Arch Nerd.

"Please be careful, Uraraka-san!" Cat Doc begins, all gentle rebuke and genuine concern. Uraraka smiles sheepishly, apologizing and lowering her head respectfully, movements now cautious and measured. As she bows, her fingers –in a loose grip just above his elbow—feather down his forearm 'til the warm weight of her palm settles soft over the back of his hand. Katsuki can't tell if the acid knots in his stomach are the result of Uraraka activating her quirk on the sly, or something infinitely stupider. "I'm afraid you'll have to get used to taking things slow, at least for a couple of weeks." The doc continues, beginning to rattle off recommendations for icing and rest and eventual massage therapy, while Katsuki does whatever the opposite of staring is at the hand folding itself around his. What he's left with is Uraraka, _holding his hand_.

Sensing both challenge and ulterior motive, Katsuki responds automatically and only to the former, defiantly reciprocating her grip – like a fucking amateur, since that's exactly what she fucking wants. Instantly, her face lights with a cutesy-devil smile, and she slides her gaze sideways to meet his eye just as his feet leave the floor. At least this time it's for sure her quirk's fault when his guts go lava twister.

 _Benevolently_ , he doesn't make a grab for the mattress or bed rails or privacy curtain, instead letting her lift him slowly overhead with the forbearance of a motherfucking _saint_. _Any other day_ , this scenario plays out very differently: shouting, explosions, the very real likelihood Uraraka throws him out the damn window –the whole fucking nine. But earlier today, in front of a packed stadium and a televised audience of probable millions, Uraraka one-punch KO'd the new-fangled fucking 'Symbol of Peace' and earned herself a little (limited-time) goodwill. She's _burning through_ that shit, but at least for the moment, he will _graciously_ endure this idiot spectacle.

Absently, he hears Cat Doc's speech skidding to a halt, and Katsuki spares a thought for whether it would technically violate doctor-patient confidentiality for her to disclose the details of Ground Zero's first – _public_ \- stint as Uravity's glowering balloon. If not, this rep-busting witness account is about to dominate the next several news cycles, and make his life an endless hell of checking the impulse to murder the press hordes sure to descend on his apartment building and set up camp.

Uraraka's beaming up at him victoriously, like she's pulled one over on him when this is obviously only happening at all because he is the fucking **paragon** of restraint. Then she blows him a kiss and winks, pleased as fucking punch, and he scowls his way through a familiar arrhythmia, wondering again when the shit _that's_ due to finally fucking _stop_.

* * *

who expected the action of this chapter to culminate in a cheap-ass deku nut-shot?

yeaaaaah, me, either. came outta nowhere. but bakugou definitely enjoyed it, the sadistic little shit. uraraka's going to be apologizing for that one for _ever_. (also, yes, i realize bakugou's witnessed deku getting socked in the junk before, but *i* like to think every time is like the first time for this trash child.)

alsoalso: if you're wondering if this ficlet's meant to suggest uraraka's deku dick-decking debut is a contributing factor in the way bakugou feels about her, then you are reading this correctly.

this was *supposed* to be just a few throw-away lines at the start of chapter five of 'feat equal' about how 'the whiplash' came to be, but once i conceived of pitting kacchako against tododeku in a doubles exhibition match, i . !

splinter stories keep flakin' off the main facade, y'all. gotta pull them shits out and release 'em back into the wild afore they work their way through my bloodstream and straight up stab-murder me in the heart. (this metaphor is 100% logic-positive!)

there may be one or two more 'codicils' in the offing, depending entirely on factors over which i have zero control. just fyi.


End file.
